The film takes place in 1964 and follows the life of Jimmy Cooper (Phil Daniels), a young London Mod. Disillusioned by his parents and a dull job as a post room boy in an advertising firm, Jimmy finds an outlet for his teenage angst by taking amphetamines, partying, riding scooters and brawling with Rockers, accompanied by his Mod friends Dave (Mark Wingett), Chalky (Philip Davis) and Spider (Gary Shail). One of the Mods' rivals, the Rockers, is in real life Jimmy's childhood friend, Kevin Herriot (Ray Winstone). An attack by hostile Rockers on Spider leads to a retaliation attack on Kevin. Jimmy initially participates in the beating, but upon realising the victim is Kevin, he berates the other attackers but does not stop them, instead riding away on his scooter.A bank holiday weekend provides the excuse for the rivalry between Mods and Rockers to come to a head, as they both descend upon the seaside town of Brighton. Jimmy plans to be noticed as a 'face', and hints to Steph (Leslie Ash) -- a girl on whom he has a crush -- that he would like her to ride with him, but she confirms plans to ride instead with Pete (Garry Cooper), an older, well-heeled Mod. To prepare for the weekend, the friends attempt to buy some recreational drugs from London gangster Harry North (John Bindon), but are cheated with fake pills. After vandalizing the drug-dealer's car from retaliation, they desperately rob a pharmacy, finding a large quantity of their favorite "blues".After an early morning group ride from London to the south coast, the friends gather on the seafront, where Jimmy first sees a flamboyant scooter-riding Mod known as Ace Face (Sting). Later in a dance hall, Jimmy suggests that he will help Steph, whose escort is now chatting to an attractive American girl, to dance with Ace Face, whereupon Jimmy plots to gain attention by climbing up on the balcony-edge and dancing with much applause, annoying Ace Face. After diving into the audience, Jimmy is ejected by bouncers. Steph's escort leaves with the American girl, and once again Jimmy attempts to get with Steph, this time for the night, but she has arranged accommodation with a female friend.The friends spend the night sleeping rough, meet up at a cafe on the following morning, then proceed along the promenade, where a series of running battle ensue. As the police corner the rioters, Jimmy escapes down an alleyway with Steph, and they have sex. When the pair emerge, they find themselves in the middle of the melee just as police are detaining rioters. Jimmy is arrested and detained with a volatile Ace Face, and later fined the then-large sum of £50. When fined with a hefty £75, Ace Face mocks the magistrate by offering to pay on the spot with a cheque, impressing the fellow Mods.Back in London, Jimmy becomes severely depressed. His mother throws him out after she finds his stash of amphetamine pills. He then quits his job, spends his severance package on more pills, and finds out that Steph has become Dave's girlfriend. After briefly fighting with Dave, the following morning his rejection is confirmed by Steph, and his beloved Lambretta scooter is accidentally damaged in a crash involving a Royal Mail parcel van. Jimmy takes a train back to Brighton, taking increasing levels of pills and becoming emotionally unstable.In an attempt to relive the recent excitement, he revisits the scenes of the riots and his encounter with Steph. To his horror, Jimmy discovers that his idol, Ace Face, in real life has a menial job as a bellboy at the Grand Brighton Hotel. As a response, Jimmy steals Ace's Vespa scooter and heads out to Beachy Head, where he rides perilously close to the cliff edge. For a time, he appears to be having an enjoyable ride in the sunshine, but then he stops the scooter and glares miserably at the sea. Finally, he crashes the scooter over a cliff, which is where the film begins, with Jimmy walking back from the cliff top into the sunset backdrop.